Vietnam's capital has extended Covid-19 restrictions for a further two weeks, as authorities launched a plan to test up to 1.5 million people for the coronavirus in higher-risk areas of the capital to contain a climb in infections, Reuters reports.

Hanoi's administration, which has ordered people to stay at home and has halted all non-essential activities since July, has now divided the city into "red", "orange" and "green" zones based on infection risk.

"Accordingly, people in red areas must shelter in place and one person of every household there will be tested three times per week," a statement from city authorities said, adding that in other zones people would be tested every five to seven days.

Hanoi authorities expect up to 1.5 million test samples to be collected in the next week. The government is eager to keep the outbreak from reaching the intensity seen in Ho Chi Minh City.